Update 2018-02-23: The version of this information that I'm keeping up to date is trycontra.com/roles.

More dances have switched to "Larks / Ravens", so here's an updated version of the chart I made before:

~312 series, ~130 weekends	Gents / Ladies	Various (series, weekends)
8 series, 5 weekends	Larks / Ravens	Berkeley, BIDA, Circle Left, Form the Ocean, Hayward, JP, LCFD Dance Camp (both coasts) Sebastapol, South Bay, Village Contra, YDW
1 series	Bands / Barearms	Rainbow Contra Dance of Western Mass, Queer Contra Chicago
1 series	Jets / Rubies	Portland ME
1 series	Leads / Follows	Brooklyn Contra

The biggest change is that [EDIT: nearly] all the "Bands / Bares" dances have switched to "Larks / Ravens", but there are also a few dances (BIDA, Sebastapol, YDW) that have swiched from "Gents / Ladies".

Update 2017-10-20: I've edited the chart above after learning that Rainbow Contra Dance of Western Mass is still using "Bands / Barearms".